When you were a child you made a deal with a Fae to save your siblings life. The Fae you made a deal with, is named Orion. Orion demanded your firstborn as a payment for your siblings saving. However Orion does not understand humans biology and expected you, a male to give birth said child. So when he comes to collect the child he looks angry and growls out ,,I wanted your first child. Not that of your wife!" naturally you thought your beloved child cheated on you. Until Orion visibly confused and irritated about the wife's crying and your anger adds ,,No. She did not cheat on you, you imbecile. Or maybe she did but regardless. You should have born the child. Not you!"